Adapter means for an underwater projectile



Dec. 24, 1968 E, NlTENsoN 3,417,719

ADAPTER MEANS FOR AN UNDERWATER PROJECTILE Filed July 6, 1966 United States Patent 3,417,719 ADAPTER MEANS FOR AN UNDERWATER PRUJECTILE Edward Nitenson, 2089 Dorchester Ave., Dorchester, Mass. 02124 Filed .luly 6, 1966, Ser. No. 563,210 2 Claims. (Cl. 114-20) ABSTRACT 0F THE DISCLSURE An underwater projectile is provided comprising an elongated hollow casing with a gas contianed within the casing. A rear wall of the casing defines a preselected area for penetration and means are located in association with the preselected area for uniformly discharging gases from the casing when the preselected area is punctured. An underwater gun is provided having means for frictionally engaging the projectile in the barrel and means for piercing an area of the projectile to permit uniform gas escape therefrom. Magazines are mounted on the barrel for feeding a series of projectiles to the barrel,

Underwater guns have been known to the art for many years. The launching and firing force for known projectiles fired by such guns are often derived from spring constructions, gas pressure chambers, pressure filled projectiles, ignitable chemical propellants and the like. Perhaps due to the nature of the water environment in which such guns are fired, it has been extremely difficult to devise a gun and projectile which permits high accuracy and precision. The projectiles of known construction are subject to unwanted fluctuations over their path of travel and do not tend to follow a substantially straight linear course.

The prior art has suggested the use of fins and various hydrodynamic guiding means incorporated on the projectiles to guide their movement over straight lines and provide for accuracy in hitting targets at long distances. However, such means often add to the weight and cost of the projectiles. Moreover, known constructions have not achieved accuracy and precision particularly where projectiles are fired for distances of twenty feet or more.

It has now been found that variations from a desired path of a projectile of the gas pressure filled type, are often due to variations in gas. flow patterns from a punctured orifice of a gas filled projectile. Commonly gas filled projectiles are merely punctured by a punching action leaving a jagged rear hole through which gas escapes to propel the projectile. The:.jagged hole is inherent in known constructions since the punching action cannot produce a perfectly round uniform cross section opening. Nonuniform gas flow from the projectiles causes erratic motion and at least slight fluctuations of the projectiles from straight line paths tending to increase water turbulence and resistance thus slowing down such projectiles and altering their course in flight.

Another disadvantage of known underwater gun con structions is their conventional single shot action. Such constructions require manual loading of each projectile which is time consuming and can be extremely dangerous when such guns are used as shark repellents or in hunting various sea forms.

An important object of this invention is to provide a means for precisely propelling a projectile underwater along a predetermined path.

Another important object of this invention is to provide a means in accordance with the preceding object comprising a projectile which is inexpensive yet extremely accurate.

Still another important object of this invention is to 3,417,719 Patented Dec. 244, 1968 rice provide a means in accordance with the preceding objects which is capable of rapidly firing a series of projectiles semi-automatically.

According to the invention, an underwater projectile comprises an elongated hollow casing containing an expansible propellant within the casing. A rear wall of the casing defines a preselected area for penetration of the casing to release the gas and thereby cause propulsion of the projectile. Means are located `in association with the preselected area for uniformly discharging gases from the casing when the preselected area is punctured. The uniform ow of gases from the casing is extremely important to avoid unwanted fluctuation during the path travel of the projectile and maintain the projectile along a linear path to achieve high target accuracy. Preferably the means provides a circular discharge orifice located behind the area to be punctured and preferably with a small expansion chamber therebetween.

The underwater gun of this invention useful for firing a series of gas-filled projectiles as previously described comprises an elongated barrel constructed and arranged to snugly receive an elongated projectile. Means are provided for frictionally engaging a projectile in the barrel and another means acts as a firing mechanism for piercing the preselected area of the projectile to permit gas escape. A magazine means is mounted on the barrel for feeding a series of projectiles thereto and a means is preferably located in the barrel for positioning each projectile in the barrel in proper firing position after feeding from the magazine.

It is a feature of this invention that the rapid reloading by means of a magazine and the accurate path of travel of the projectile render the means of this invention particularly useful as a shark repelling device. Thus, a series of missiles can be accurately fired in succession to drive off sharks underwater. The projectiles can also be used with suitably designed configurations for underwater fishing.

The above and other objects, features and advantages of the invention will be better understood from the following specification when read in connection with the accompanying drawings in which:

FIG. l is a side view partially in cross section of an underwater gun and projectile in accordance with the preferred embodiment of this invention;

FIG. 2 is a top view of a portion thereof;

FIG. 3 is a cross sectional view through line 3-3 thereof;

FIG. 4 is a cross sectional view through line 4-4 thereof; and

FIG. 5 is a cross sectional view through line 5 5 thereof.

Turning now to the drawings, an underwear gun in accordance with this invention is illustrated generally at 10 in FIG. l and comprises a hand grip 11 forming a portion of stock 12 to which is attached a cylindrical barrel 13 having a detachable magazine clip 14 carrying a plurality of projectiles 15.

The projectiles 15 are preferably specially designed and form an important part of the present invention. These projectiles comprise a conventional elongated cylindrical casing 16 having a blunt rounded forward end 17 and a tapered threaded rear end 18. A rear area 19 at the tip of the threaded end 18 acts as a preselected area which can be punctured to release compressed gases contained within the hollow casing 16.

Casings such as 16 are conventionally used in spear fishing guns and are readily available. One particular type of casing 16 eminently suitable for use in the present invention is known as US. Divers Cartridge and has an outside diameter of about 0.744, a length of about 31A and contains a compressed gas having a pressure of about 850 pounds per square inch at 70 F. and an over-all weight of about 2 ounces.

Attached to the rear end of the casing 16 is an adapter 20 comprising a cylindrical section defining a threaded end 21 threadably engaged with end 18 and a generally cylindrical elongated expansion chamber 22. Beyond the expansion chamber 22 leading to the extreme rear of the adapter 20 is a circular bore 23 providing a uniform elongated passageway and defining an orifice at the extreme end of the adapter having a circular configuration coaxial with the longitudinal axis of the projectile 15. As can readily be seen from the drawing, when the preselected area 19 is punctured, gases escape from the casing 16 into the expansion chamber 22 and are funneled out of the passageway 23 and rear orifice through a circular opening providing for a uniform escape of the gases, i.e., the expansion of the gases beyond the end orifice and flow from the end orifice follows a circular cross section symmetrical about the longitudinal axis of the casing and symmetrical about the linear path of travel of the projectile. It has been found that merely puncturing the preselected area can never provide a uniform symmetrical orice providing for uniform flow. Thus, if no adapter is used and the end area 19 punctured, variations in symmetry of flow of the gases from the chamber cause fluctuation during the flight path of the cartridge. On the other hand, when a symmetrical orifice end opening is used, the uniformi flow pattern is instrumental in providing for elimination of fluctuation and straight line movement of the casing 16 along its trajectory path.

While a preferred embodiment of the adapter 20 is illustrated and described, many -modications can be made therein. For example, it is only necessary to provide for uniform escape of the gas at the extreme end of the projectile by the use of a symmetrical balanced opening about the axis of the projectile. Preferably the opening has an area no greater than that of a circle of 1/8 diameter. Thus, star-shaped symmetrical openings, or other shaped openings can be used. In some cases, the expansion chamber 22 can be eliminated or changed in configuration. Similarly, the screw thread means can be substituted with any known attachment means or the orifice end can be fabricated directly on the casing 16 beyond the preselected area 19.

In addition to variations in the adapter, the casing 16 can be modified as desired. It is preferred that the casing be no longer than 7" in length to maximize eiciency in small hand-held gun arrangements. The blunted end 17 can be pointed or otherwise shaped to adapt it for fishing if desired. The blunted end can be provided with an attached explosive head for exploding on contact. It is unnecessary to use guidance fins in View of the hydrodynamically-shaped casing symmetrical about its longitudinal axis although such fins may be provided if desired. It should be understood that even the blunted end projectile described above provides sufficient force to deter a shark at a distance at least as great as 2O feet.

A plurality of projectiles 15 are preferably carried in a conventional spring loaded magazine 14 for semi-automatic feeding to the gun barrel 13. The magazine 114 is preferably generally rectangular having a spring pusher section '25 constantly urging the projectiles upwardly. A fiat slide plate 26 is provided fitting in notches 27. The plate 26 covers the projectiles and maintains them in place before attachment of the magazine to the gun 110. When the magazine is clipped to the gun barrel underlying a slot 28, by conventional attachment means not shown, the plate 26 is slid forwardly to a forward bracket 29 during use of the magazine allowing projectiles 15 to be pushed upwardly into the barrel directly above the magazine.

The gun barrel 13 is provided with a slot 30 and a split ring 31 overlying the slot. Split ring 31 is suitably located for axial sliding by projections and notches 32 as best shown in FIG. 3. The ring 31 has an extension portion 33 fully covering the slot when the ring is positioned in its forward position as shown in FIG. l. Covering of the slot prevents water and gas escape which could be detrimental to the path of the projectile. The ring 31 carries a downwardly extending pin 35 spring loaded by coil spring 36 to its rupper position.

In use, when a cartridge 15 is automatically positioned within the barrel 13, the ring 31 is slid to its forward position, pin 35 depressed engaging the forward end 17 of the projectile. Movement of the pin rearwardly by the hand moves the projectile rearwardly into its Vfiring position as will be described.

The firing mechanism of the gun 10 comprises a cylindrical member 36a attached to the rear end of the barrel 13 as by screw threads 37. Barrel 13 and member 36a are attached to the stock 12 by conventional means such as bolts not shown. Member 36a has an axially aligned adapter receiving section 38 and carries a threaded shank 39 adapted to be screwed down by handle 40 into frictional engagement with the tip of the adapter as best shown in FIG. 1. The shank 39 holds the projectile in a frictional fit within the barrel and preferably exerts just enough pressure to maintain the projectile in place while piercing of the preselected area 19 is carried out by a firing pin 40.

The firing pin 40 is axially algned wth the barrel and member 36a and comprises a pointed end `41 for piercing of the wall 19 to a preselected depth whereupon the shoulder 42 meets with the end of the adapter section urging the adapter towards the opened end of the barrel overcoming the frctional force applied by the shank 39.

The pin 40 is slidably mounted for reciprocation along the axis of the gun barrel by a coil spring 43 abutting a stop 44 and fixation collar 45 which is in turn attached to the member 36a. Thus, the spring 43 constantly urges the firing pin to the position shown in FIG. 1.

The hand grip 11 carries an actuator 50 which is spring loaded by spring 51 about pivot pin 5'2 to the position shown in FIG. 1. Preferably within the spring 51 is a shaft 53 having one end pivoted to the hand grip at 54 and a second end slidable within a suitable groove 55 in the actuator or trigger 50. Upon gripping of the actuator 50 and rapid pulling toward the handle by the hand of a user, the firing end 56 contacts the stop 44 and rapidly pushes the pin 40 to its piercing position.

A bore 60 is provided in the member 36a permitting communication between the end of the barrel and the outside. The outside end of the bore is covered by a circumferentially rotatable slip ring 61 having a bore `62 therein adapted to mate with bore 60 upon rotation to the position shown in FIG. 4. Upon rotation out of the position shown in FIG. 4, bore 62 is displaced to the side and bore 60 covered substantially preventing cornmunication between the outside and the barrel end. Slip ring 61 is adjusted to the position shown in FIG. 4 when pin 35 is used to move a projectile rearwardly. Thus, during this movement, passageway 60 allows expulsion of water within the barrel. When the projectile is in its ring position and during firing, the slip ring 61 is rotated to close the passageway 60. Closing of the passageway 60 has been found extremely desirable to concentrate the expanding gases within the gun barrel during launching or tiring and thereby add substantial momentum to the flight of the projectile.

Turning now to the method of operation of a preferred embodiment of this invention, the gun barrel 13 has an inside diameter of approximately 0.750 inch and a length of about 14 inches. A 2-ounce U.S. Divers Cartridge as previously described, having a length of about 3% inches and a diameter of about 0.744 inch was used with an adapter 1% inch long having a passageway 23% inch long with a uniform diameter of 1/16 inch. Expansion chamber 22 is 1A inch long and has a diameter of 1A; inch. A magazine clip 14 containing six cartridges was placed in position on the gun barrel and the slide plate 26 pushed forwardly to engage the bracket 29 allowing a cartridge to be automatically positioned in the barrel. Pin 35 was depressed and moved rearwardly to locate a projectile in the position shown in FIG. 1 with ring 61 suita'bly positioned. The firing pin was actuated by the actuator S0 t0 provide a hole of about 3/16 inch diameter in the preselected area 19. Immediately upon actuation of the firing pin to cut the hole, the projectile 15 was pushed out of frictional engagement with the shank 39 and launched from the gun barrel by the expanding gas covering 20 feet underwater in about 3 seconds alonng a substantially straight line path to hit a target with substantial force suflicient to stun a shark. As the first projectile left the gun barrel, a second projectile 15 was positioned therein and the launching operation repeated until each of the cartridges were rapidly and accurately fired.

While specilic embodiments of this invention have been shown and described, it will be obvious to those skilled in the art that many modifications thereof are possible. For example, the ring pin arrangement for tiring the cartridge can vary greatly. In some cases, thel firing pin will be preloaded by a spring or other means in the forward direction rather than the rearward direction. Thus, upon tripping of a suitable lever, the spring or other means will add substantial force to the firing pin enabling substantially instantaneous piercing of the preselected' area. Similarly, the member 36a may take other forms. In all cases, it is desirable to use a magazine feed for rapid firing of a series of projectiles.

The frictional means vary vary. In some cases, the

diameter of the casing 16 can be dimensioned to provide for frictional engagement of the casingv with a preselected area of the gun barrel and thus enable elimination of the frictional means 39. Similarly, the means for locating the projectile adjacent the firing mechanism can `be varied and in some cases member 36a can be slid into engagement with the projectile rather than vice versa.

The means of attachment of the adapter can vary. Thus, a force tit joint can be used in place of a screw thread.

The size of the hole formed by `the firing pin 41 can vary depending upon the distance of travel desired and the force at a given distance desired. Thus, a large hole -provides faster travel over a shorter distance than a small hole. Similarly, variation in the diameter of end orice 23 will affect speed and distance. If desired, the tiring pin can be made adjustable to provide predetermined travel of its point to form a desired size open` ing. In all cases, the projectile does not move until the shoulder of the firing pin pushes it past the friction holding means.

In view of the many modifications possible, this invention is to be limited only by the spirit and scope of the appended claims.

What is claimed is:

1. An underwater projectile comprising an elongated hollow casing,

an expandable propellant gas contained within said casing, a rear wall of said casing delining a preselected area for penetration of said casing to release said gas,

an adapter defining a passageway with an end opening axially aligned with the axis of said casing,

said passageway delining an expansion chamber for said gas prior to discharge of said gas from said end opening whereby said gas can be uniformly discharged from said casing when said preselected area is punctured by entrance of a puncturing means into said passageway and said preselected area.

2. An underwater projectile in accordance with claim 1 wherein said passageway is provided aligned with said preselected area and said passageway defines said end opening symmetrical about the axis of said casing having an area no greater than that of a circle: having a diameter no greater than about 1A; inch.

References Cited UNITED STATES PATENTS 279,539 6/1883 Chamberlain IGZ- 49.3 466,056 12/1891 Bott 10Q-49.3 3,052,451 9/1962 Hamrick 42-1 BENJAMIN A. BORCHELT, Primary Examiner.

U.S. Cl. X.R. Ll2--l; 89--l; IGZ-49.3 

